RENAL BOTRYOMYCOSIS MIMICKING RENAL CELL CARCINOMA

Abstract

Botxyomycosis is characterized by a chronic suppurative lesion with distinctive fungus-like grains similar to sulfur granules in actinomycosis.1 The integumentary and visceral forms are recognized.’ Only 2 of the previously reported 6 renal botryomycosis cases were isolated, which simulated renal cell carcinoma radiologically and clinically, and actinomycosis and mycosis pathologically.2.3 We report on a patient in whom isolated renal botryomycosis was preoperatively diagnosed as renal cell carcinoma and who underwent radical nephrectomy. CASE REPORT A 57-year-old man presented with right renal colic and fever 4 months in duration. He had a 10-year history of type I1 diabetes mellitus and had undergone extracorporeal shock wave lithotripsy elsewhere for right ureteral stones on 2 occasions. Physical examination demonstrated tenderness and pain on palpation of the right lumbar region. Abdominal ultrasonography and computerized tomography of the abdomen revealed a solid 5 cm. mass at the lower pole of the right kidney (fig. 1). Escherichia coli was cultured from the urine. The preoperative diagnosis was renal cell carcinoma and right radical nephrectomy was performed. The mass invaded the perirenal adipose tissue, psoas muscle and liver at surgical exploration, and it was completely resected. Pathological evaluation demonstrated that the mass consisted of confluent abscesses extending into perirenal adipose tissue. Centrally these abscesses contained Gram-negative bacilli surrounded by amorphous eosinophilic material, termed the Splendore-Hoeppli phenomenon (fig. 2). Histochemical stains (Gomori methenamine silver for actinomyces and fungi, and Brown-Hopps tissue gram stain) confirmed the diagnosis of botryomycosis. Postoperatively the patient was treated with 2 gm. cephalosporin daily and convalescence was uneventful.